The present invention relates to a method for making silicone compositions, more particularly to compositions comprising a silicone polymer network comprising cross-links derived from epoxide or oxirane moieites.
The personal care industry thrives on being able to deliver multiple performance products based on mixtures of several components, with each having performance characteristics important to or desirable in the final formulation. One desirable characteristic is the ability to provide a silky initial feel derived from low molecular weight silicones, such as for example, octamethylcyclotetrasilioxane or decamethylcyclopentasiloxane, in the formulation while maintaining a high, but shear-thinnable viscosity. While these low molecular weight silicones provide the desired feel characteristics, they are also low viscosity, highly flowable liquids. Thus they are not easily held in a formulation, preferring rather to separate and flow out of a given container or flow uncontrollably across the skin when used in a specific application. Further, it desirable to achieve an initial silky feel while providing a smooth, low-residue feel upon dry-down. Polymeric silicone gels prepared in volatile silicone have been found to deliver desirable initial feel of volatile, low viscosity silicones to formulations while at the same time provide high viscosity and a smooth silky feel on dry-down, see for example, U.S. Pat. Nos. 5,760,116, 5,493,041 and 4,987,169.
Such polymeric silicone gels have typically been made by the hydrosilylation reaction, which requires the use of both SiH functional groups and terminal olefinic groups to form crosslinked siloxane polymers. Thus only siloxane structures that can incorporate silylhydride groups and optionally, vinyl functional siloxane groups, can be utilized in making these materials. Further this method of generating crosslinked siloxane polymers limits the range of desirable organofunctional groups that may be incorporated into the polymeric structure to create additional performance advantages in complex formulations. Thus attempts to include organofunctional groups into the crosslinked siloxane polymer include unsaturated organic groups compatible with the hydrosilylaton reaction.
The present invention provides for a method of making a cosmetic composition comprising the reaction products of
MaMHbMEcDdDHeDEfTgTHhTEiQj
where
M=R1R2R3SiO1/2;
MH=R4R5HSiO1/2;
ME=R6R7RESiO1/2;
D=R8R9SiO2/2;
DH=R10HSiO2/2;
DE=R11RESiO2/2;
T=R12SiO3/2;
TH=HSiO3/2;
TE=RESiO3/2; and
Q=SiO4/2;
where R1, R2, R3, R8, R9 and R12 are independently monovalent hydrocarbon radicals having from one to sixty carbon atoms; R4, R5 and R10 are independently monovalent hydrocarbon radicals having from one to sixty carbon atoms or hydrogen; R6, R7, R11 are independently monovalent hydrocarbon radicals having from one to sixty carbon atoms or RE; each RE is independently a monovalent hydrocarbon radical containing one or more oxirane moieties having from one to sixty carbon atoms; the stoichiometric subscripts a, b, c, d, e, f, g, h, i, and j are either zero or positive subject to the following limitations: a+b+c greater than 1; b+e+h greater than 1; c+f+i greater than 1; b+e+h greater than c+f+i; and when d+e+f+g+h+i+j=0, a+b+c=2. In a preferred embodiment the reaction product of the present invention is a polyether siloxane copolymer network. In another preferred embodiment the reaction product of the present invention is a polyether siloxane copolymer network swollen with a volatile low molecular weight silicon containing compound. These compositions are useful for a variety of personal care compositions.